Hawaii's famous “happy-face” spider has a surprising relative

Now, researchers from the Forest Research Institute and the Regional Museum of Natural History have identified a new species in the mountains of Uttarakhand, India. Because of its striking resemblance to the Hawaiian species, they named it Theridion himalayana, or the Himalayan Happy Face Spider.

An Accidental Spider Discovery

"The discovery was accidental because our survey was [originally] on ants," said Devi Priyadarshini, a scientist at the Regional Museum of Natural History and coauthor of the study.

"But my co-author [Ashirwad Tripathy] kept sending me spiders from high altitude regions for identification. So, one fine day, when he shared this image from the underside of a Daphniphyllum leaf, I froze in shock because I had seen the Hawaiian spider during my master's program itself, and I knew instantly we had a jackpot because of its striking resemblance. I asked him to send all morphs that he found, and that led to the discovery in the next few months, from October 2023 onwards."

Priyadarshini said she has long been interested in studying spiders that live at high elevations because those environments differ greatly from the lowland plains in both vegetation and landscape.

"This almost came across as a gateway to look at other polymorphic species from this region."

Ashirwad added that broader field surveys could uncover even more variations within the species.

Named After the Himalayas

The newly discovered spider was found at elevations above 2,000 meters, and its species name, himalayana, honors the mountain range where it was discovered.

"The name Himalayana was decided as the species name because we both wanted to pay our respects to the mighty Himalaya mountain ranges, which have been standing tall not just guarding our country but also holding a plethora of biodiversity within them," Ashirwad said.

"Since this spider was the first polymorphic from this region, we decided to make it an ode to the amazing mountain ranges."

DNA Confirms a New Spider Species

The findings, published in the open access journal Evolutionary Systematics, documented 32 different color forms, or "morphs," collected from three locations in Uttarakhand: Makku, Tala, and Mandal.

Genetic analysis showed the new spider differs from Hawaii's Happy Face spider by about 8.5%, confirming that Theridion himalayana represents a separate evolutionary lineage that developed independently in Asia.

The Mystery Behind the Spider's Smile

Although the colorful smile like markings make these spiders instantly recognizable, scientists still do not know why they evolved.

"The reason behind the expression of polymorphism is also very complex and unique," Priyadarshini explained.

"These patterns definitely help them survive better in the wild, which is understood prima facie, but why do they resort to such patterns on their back, and what functional role in their life cycle does it exactly serve is yet to be deciphered. This is definitely indicative of a deeper genetic mystery."

Ashirwad also noted that the spiders were found alongside other small creatures with similar color patterns, suggesting there may be broader ecological or evolutionary factors at work.

A Curious Link to Ginger Plants

Researchers also discovered another unexpected similarity between the Himalayan and Hawaiian species. Like their Hawaiian counterparts, the newly identified spiders are commonly found on ginger plants (Hedychium species).

Because ginger is not native to Hawaii, the shared preference raises new questions about the spiders' evolutionary history.

"How did the spiders choose an invasive species and ginger exactly?" Priyadarshini noted.

"If T. himalayana is an elder cousin of T. grallator, although discovered 125 years later! Although this sounds like a tall claim now, it will be our further scope of work to establish any missing links, if at all, through Hedychium sps."